Landslide monitoring

Synthetic Aperture Interferometry (InSAR) is used to monitor ground surface deformations corresponding to phase differences generated from interference fringes. DInSAR limitations and challenges are linked to the SAR properties and the field conditions (especially in Alpine environments) leading to spatial and temporal decorrelation of the SAR signal. High temporal decorrelation can be caused by changes in vegetation (particularly in non-urban areas), atmospheric conditions or high ground surface velocity.

The slow-moving Corvara landslide located in Val Badia, which is active since the last 10,000 years, has been monitored by InSAR using Sentinel-1 images. Persistent Scatterer Interferometry (PSI) processing requires stable reflecting objects, such as houses or blocks. As these are not available on the Corvara landslide, artificial corner reflectors (CRs) have been installed to have reliable permanent scatterers. Small Baseline Subset (SBAS) InSAR results in combination with other sensors and techniques enables the recognition of the kinematic and displacement field of the Corvara landslide (Schlögel et al. 2017a; Schlögel et al. 2017b). There, the slope displacement rates are found to be highly unsteady and may reach several meters a year. Other landslides in the area of South Tyrol are going to be investigated using InSAR techniques.